1. Field of the Invention
This invention relates to vehicle towing apparatus and methods for same. More specifically, the field of this invention relates to a steel hitch at the tow vehicle that will extend, swivel and automatically lock the towed and towing vehicles together in a simple and efficient manner. Additionally the field of this invention relates to a simple interchangeable draw bar that can be interchanged from ball to pintle or similar type coupling mechanisms for towing purposes.
Explanation of Terms
Set out below are brief descriptions of certain relevant terms which further the understanding of the invention. These terms provide a basis for a detailed teaching of the improvements of this invention in the relevant arts. Such terms are not intended to replace the claims but rather serve as helpful guides in understanding our novel improvements in these arts.
Centering Draw Bar
Towing is accomplished by a steel draw, pull or tow bar that has at its exposed end an opening for receiving a coupling device such as a ball/socket or a pintle hook. (See below.) The invention draw bar has four aligned openings with the tow-securing apparatus (whether drop socket or pintle) at the exposed rearmost position. The other three aligned openings in the draw bar receive, in order, a locking pin and a pair of movement control guide pins. The draw bar is moveably pinned to swing in an arc left to right, slide forward and back while being automatically lockable and manually releasable as desired.
Coupling Between Tow and Towed Vehicles
A ball and “lift and drop” coupling socket has the receiving socket on the to-be-towed (“towee”) vehicle and the ball on the towing vehicle. A pintle lock type has both ball and socket on the tow vehicle and is self closing upon contact with a receiving ring or opening on the to-be-towed vehicle. In the latter event, the receiving opening—say a steel ring on the towee vehicle is large enough in diameter and sturdy enough that contact with the pintle hook at the exposed end of the bar will allow the ring to drop over the pintle hook ball. Such pintle hooks are well known and many examples may be found that explain and depict them. For example, in the 2004 Issue of Northern Hydraulics at Catalog page 220 five different models are shown together with the flat steel adapter. In either event, however, the coupling end of the draw bar becomes selectively fastened to the receiving apparatus on the towee vehcile.
Adjustable Hitch Housing
A hitch housing for the tow provides limited and unique arc and extending/retracting freedom of movement for the draw bar during the coupling process. Movement control pins, once inserted via the top cover and retaining the draw bar within a pocket in the housing, are guided within confines established by a pair of aligned housing openings in the bottom cover. Together the pins and openings allow the draw bar a limited and unique freedom of movement that permits easy centering and automatic coupling between the tow and a towed vehicle.
Draw Bar Housing Openings
Two pins within the housing are located with side to side and back to front movement in a pair of housing openings. Taking the rear end of the tow vehicle as a reference point, the rearmost opening is a smaller triangular-shaped “piece-of-pie” opening; whereas the larger front opening is essentially a smooth heart-shaped opening. These openings have their points aligned along the center, or tow line, of the hitch for advantageous locking and movement purposes. The arc of the rear opening defines the amount of swivel and acts as a side to side pin guide. The arc at the base of the rear opening is matched by a reversed direction arc that forms the dip of the heart shaped front opening. Movement control pins trace out a pattern of movement within these housing openings in order to accomplish the novel features of this invention.
Automatic Locking Pin
A third opening in the housing is located at the extreme front end of the mounting plate. This locking pin opening is aligned with the points on the pie and heart shaped freedom-of-movement openings. Housed in the locking pin opening is a raised spring loaded taper pin that has a cross piece for manually lifting upon a coupling release. And, the taper pin acts as a detent which, being spring loaded, drops into a receiving opening in the draw bar for automatic locking purposes. Made of cold rolled steel, it is strong to bear the tow load.
2. Description of Prior Art
Towing hitches are, of course, well known. Also well known is the great difficulty in aligning the tow ball and the receiving socket, or cap, between the towing vehicle and the towed vehicle. Whether it is a pickup truck and a boat trailer, or a semi-sized RV and the trailing auto to be towed along behind the RV, such alignment poses severe problems for many people. A successful coupling of the two vehicles is normally a series of driver back and forth and turning right, turning left, inching forward and jerking back.
To add to the problem, these are mostly blind movements while someone else, in an almost equally blind and potentially dangerous position, tries to signal the desired movements necessary for a successful coupling to take place. Further still, there are also height adjustments needed along with the arc and back and forth in plane movements.
Highly summarized, a successful coupling between the two vehicles may generally be summarized as a frustrating and stress raising situation. In the RV world especially, men or women drivers being what they are, husband and wife both dread this connecting process.
Then, one must also add to the frustration, the weight of the towed vehicle. Take, for example, a boat on a trailer. Generally speaking after a try or two by the driver of the towing vehicle, the tow ball is only slightly off line, but the weight of the to-be-towed vehicle prevents manual movement as needed for an easy and successful coupling of the two vehicles.
Commercial sized vehicles have such a bulk and mass of steel that they often must use additional leverage provided by hydraulic rams or the like during the process of coupling together such very large vehicles. They are today a size once thought not possible. Yet such vehicles must still be connected together by some form of a tow hitch. It is a serious problem that, prior to the advent of this invention, remained unsolved.
This invention presents novel operational principles that are equally applicable to today's gigantic-sized earth moving equipment as it is to pickup trucks and boat trailers. Farm implements, bulldozers, excavators are among the many vehicles which will greatly benefit by the novel features presented herein.
In general then, what has not yet been provided, in order to fill a long sought for need, is a flexible, easy apparatus and method for connecting a tow hitch between vehicles. The invention provides a novel solution to this long sought for need by featuring a limited but highly successful freedom of movement in a confined amount of swivel and back/forth adjustments with automatic locking and manual dis-engagement to boot.